110vac single to 220vac 3 phase VFDs

[tootalew]

I need to learn a bit more about VFD's that take 110vac single phase input and convert to 220vac three phase out. My main concern is amps.

I have a Hitachi L100 1/2 HP unit that takes 110vac and the plate on the side reads that it outputs 220vac 2.6 amps. The input required reads 110vac 10 amps. The amps needed on the input side are approximately 4 times the output.

Can I use 4x as a general rule of thumb when dealing with these types of VFDs?

I too have a 1.5kw (2 HP) spindle coming from china. It needs 220vac 3 phase and about 6 amps to run. I will be buying a 110vac VFD here in the states with english instructions. My question is...

Will I need 24 amps on 110vac line in order to run this spindle and VFD?

also..

Would it be better to use a VFD that is over rated (say a 2.5 of 3 HP)?

[Al_The_Man]

I am a bit leery about running 220v motor off 120 for this reason, even some 220v 1 ph in recommend de-rating on 1 ph.
Is there no way you can run a 240v line?
Al.

[tootalew]

Al,
My memory must be going, I thought my box was full, but I do have space for more circuits.

I am not sure I understand de-rating. What I think your saying is going from single to three phase, there will be lost amps. Would you mind going into a bit more detail on derating?

I do have a brother that is an electrician (residential). I am going to have him come over and I think we will just a run 220 line with 10ga it is going to be about a 50' run.
This way I can have 30amp 220 line, and all my troubles will be gone, and I can kick myself in the rear end for not buying a larger HP spindle.

[Al_The_Man]

If your Bro is an electrician you have it made, for maybe a couple of 12's.
De-rating is where a VFD is say rated for 3hp, when using 3 ph supply, a 3 hp motor can be used, no de-rating, but if a de-rating figure is shown for 1 phase use, then you may require a 5hp VFD to power the 3hp motor.
The reason being that the DC power supply that is derived from the input power is much more efficient (less ripple etc) than that derived from single phase.
Al.

[tootalew]

Al,
Thanks for the explanation. Even though my brother is an electrician, and I will have him here when I do this, hooking up a 220 circuit is not brain surgery. What is nice, is that he have all the proper tools and experience to run the conduit.